1. Field of the Invention
The present invention relates to a coaxial electrical connector, especially a right angle coaxial electrical connector.
2. Description of the Related Art
As for the right angle electrical connector, the one disclosed in JP 2001-43939 is known.
As shown in FIG. 4, the connector 50 of the Patent Reference is fitted and connected onto the counter connector 60, which is arranged on a circuit board P, in the direction vertical to the circuit board.
The counter connector 60 has a cylindrical outer conductor 61, a center conductor 62 arranged in the center of the outer conductor 61, and a dielectric 63 which is molded between those conductors as a unitary piece. The outer conductor 61 is formed to have a cylindrical shape by rolling and jointing two edges of a metal sheet piece. The outer conductor 61 has a locking groove 61A on the outer circumferential surface. The center conductor 62 has a rod-like contact section 62A, and a connecting section 62B which is formed as an L-shape arm extending from the lower end of the contact section 62A. The dielectric 63 is arranged only in lower portion of the counter connector 60. Above the dielectric 63, an annular receiving space is formed between the outer conductor 61 and the contact section 62A of the center conductor 62.
The outer conductor 51 of the connector 50 which is fitted and connected onto the counter connector 60 has a cylindrical fitting section 51A, a cover section 51B, a frame-like section 51C, and a surrounding section 51D. The outer conductor 51 is made by punching a metal sheet, and then bending it to form the shape. As also shown in FIG. 5, the cylindrical fitting section 51A has a jointing section 51A1 at its upper half portion, and has a cylindrical shape. An annular protrusion 51E for locking the fitting of the connectors is provided on the inner surface of the cylindrical fitting section 51A by making an annular groove on the outer surface of the cylindrical fitting section 51A. A plurality of slits 51F is provided at the lower half portion of the cylindrical fitting section 51A along its circumferential direction, so as to cross the annular protrusion 51E. The frame-like section 51C is provided so as to protrude in the radial direction of the fitting section 51A from a part of the upper portion of the fitting section 51A.
The outer conductor 51 holds the dielectric 52, while the dielectric 52 holds a terminal 53, which is a center conductor of the connector 50. As shown in FIG. 5, the cover section 51B and the surrounding section 51D of the outer conductor 51 are provided opposite the frame-like section 51C in the radial direction, and extend upward from a circumferential wall of the cylindrical fitting section 51A. After the dielectric 52 and the terminal 53 which is already connected to a cable are held in the cylindrical fitting section 51A, the cover section 51B and the surrounding section 51D are bent downward for 90 degree, as shown in FIG. 4. The cover section 51B and the cylindrical fitting section 51A are connected via a narrow linking section 51G, where the cover section 51B is bent. The dielectric 52 holds the terminal 53, and has a terminal hole 52A to house a spring contact section 53A of the terminal 53. The dielectric 52 also has a tongue 52B which can be bent upward at its base and a cable receiving section 52D having a cable guiding groove 52C.
In this connector 50, as shown in FIG. 5, after the core-wire C1 of the coaxial cable C is connected by soldering onto the upper surface of the terminal 53, the contact section 53A of the terminal 53 is inserted into the terminal hole 52A of the dielectric 52. Then, the outer conductor 51 is bent at the linking section 51G while pushing the tongue 52B of the dielectric 52 (See FIG. 4), and then the surrounding section 51D is bent so as to surround the frame-like section 51C and tightly hold the cable C.
Once the connector 50 is fitted onto the counter connector 60, the contact section 53A of the terminal of the connector 50 contacts with the center conductor 62 of the connector 60 by pinching it. While the cylindrical fitting section 51A of the outer conductor 51 of the connector 50 enlarges its diameter, it contacts with the outer circumferential surface of the outer conductor 61 of the connector 60, and the connector 50 is locked not to come off by the fitting of the annular protrusion 51E to the annular locking groove 61A.
In recent years, the size of electronic devices has been dramatically reduced, and electronic components used for a circuit board in such electronic device have been required to have a low profile. Especially in the right angle connector shown in FIGS. 4 and 5, the dimension of the connector 50 in the height direction, i.e. the dimension in the fitting direction, has to be reduced.
While the outer conductor 51 of the connector 50 has to have enough rigidity to maintain the shape of the cylindrical fitting section 51A, it also has to have enough elasticity to be capable of enlarging its diameter when the connector 50 is fitted to the counter connector 60. To satisfy those contrary requirements, as shown in FIG. 5, the cylindrical fitting section has the jointing section 51A1 at its upper half portion to maintain its cylindrical shape so as to have rigidity, and has slits at its lower half portion so as to have elasticity in the direction of enlarging the diameter. In other words, the cylindrical fitting section has to have upper and lower portions which have different functions, and therefore the dimension of the connector in the height direction has to be large.